Notch 1 signaling pathway is the potential target of novel anticancer drugs for the treatment of human nasopharyngeal cancer

Activation of Notch signaling pathway in cancer stem cells plays a crucial role in the regulation of self-renewal and maintenance of side population cells. In the present study, we have identified cancer stem like 2.7% side population cells from nasopharyngeal carcinoma samples whose prevalence was significantly reduced to 0.3% upon verapamil treatment. The protein level of Notch1 and Hes-1 are highly up-regulated in fluorescence-activated cell sorting purified side population cells and thus leads to the elevated expression of stem cell surface proteins (Oct-4, Sox2 and Nanog), which are essential for side population cells self-renewal. In addition, these nasopharyngeal carcinoma side population cells are CD133 and CD44 positive and they possess enhanced cell proliferation rate, highly tumorgenic and invasive. Our findings suggest that Notch1 signaling is a potential target of novel anticancer drugs, which could efficiently target and eradicate the cancer stem cells.